[PATCH v3 14/14] usb: dwc2: Add exit partial power down before removing driver

From: Artur Petrosyan
Date: Thu Apr 08 2021 - 05:46:25 EST


When dwc2 core is in partial power down mode
loading driver again causes driver fail. Because in
that mode registers are not accessible.

Added a flow of exiting the partial power down mode
to avoid the driver reload failure.

Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@xxxxxxxxxxxx>
---
Changes in v3:
- None
Changes in v2:
- None

drivers/usb/dwc2/platform.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 5f18acac7406..b28b8cd45799 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -316,6 +316,15 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
static int dwc2_driver_remove(struct platform_device *dev)
{
struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
+ int ret = 0;
+
+ /* Exit Partial Power Down when driver is removed. */
+ if (hsotg->in_ppd) {
+ ret = dwc2_exit_partial_power_down(hsotg, 0, true);
+ if (ret)
+ dev_err(hsotg->dev,
+ "exit partial_power_down failed\n");
+ }

dwc2_debugfs_exit(hsotg);
if (hsotg->hcd_enabled)
@@ -334,7 +343,7 @@ static int dwc2_driver_remove(struct platform_device *dev)
reset_control_assert(hsotg->reset);
reset_control_assert(hsotg->reset_ecc);

- return 0;
+ return ret;
}

/**
--
2.25.1